Cal. Rev. & Tax. Code § 5096.7
If taxes have been paid on property acquired by negotiated purchase by any public entity designated in Section 5081 after the commencement of the fiscal year for which the taxes are a lien on the property, the portion of such taxes which are allocable to that part of the fiscal year which begins on the date of apportionment determined pursuant to Section 5082 and made uncollectible if unpaid by virtue of Section 5086, shall be deemed erroneously collected and shall be refunded to the person who has paid the tax, where the person was not otherwise reimbursed for that portion of the taxes by the public entity which acquired the property.
Refunds under this section shall be applicable to taxes paid on either the secured or unsecured rolls.
Ca. Rev. and Tax. Code § 5096.7